[Lowfer] Downconverter for Software Defined Radio

[Lyle Koehler]

Bob, according to the Mini-Circuits catalog, both the TUF-3 mixer and the
physically larger SBL-3 are rated only at +1 dBm RF. With a conversion loss
on the order of 6 dB, you'd need to use one of those MMIC amplifiers to get
back up to a couple of milliwatts output for an HF to LF transverter.

By the way, I believe the programmable logic device (PLD) that is used to
generate the quadrature LO signals in the Time Machine can be replaced by a
74AC74 or 74HC74 Johnson counter as shown in the QEX software defined radio
articles (also available via the FlexRadio web site). The PLD sounds like a
neat way to go, but I don't know what it takes to program one.

Lyle, K0LR